Forecasting F10.7 with solar magnetic flux transport modeling

A new method is presented here to forecast the solar 10.7 cm (2.8 GHz) radio flux, abbreviated F-10.7, utilizing advanced predictions of the global solar magnetic field generated by a flux transport model. Using indices derived from the absolute value of the solar magnetic field, we find good correlation between the observed photospheric magnetic activity and the observed F-10.7 values. Comparing magnetogram data observed within 6 hours of the F-10.7 measurements during the years 1993 through 2010, the Spearman correlation coefficient, r(s), for an empirical model of F-10.7 is found to be 0.98. In addition, we find little change in the empirical model coefficients and correlations between the first and second 9 year intervals of the 18 year period investigated. By evolving solar magnetic synoptic maps forward 1-7 days, this new method provides a realistic estimation of the Earth-side solar magnetic field distribution used to forecast F-10.7. Spearman correlation values of approximately 0.97, 0.95, and 0.93 are found for 1 day, 3 day, and 7 day forecasts, respectively. The method presented here can be expanded to forecast other space weather parameters, e.g., total solar irradiance and extreme ultraviolet flux. In addition, near-term improvements to the F-10.7 forecasting method, e.g., including far-side magnetic data with solar magnetic flux transport, are discussed. Citation: Henney, C.J., W.A. Toussaint, S.M. White, and C.N. Arge (2012), Forecasting F-10.7 with solar magnetic flux transport modeling, Space Weather, 10, S02011, doi:10.1029/2011SW000748.